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101.
Two-dimensional HOHAHA and ROESY nuclear magnetic resonance techniques are used to obtain complete proton resonance assignments and to perform a conformational investigation of the neuropeptide neurotensin (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) in aqueous solution, methanol, and membrane-mimetic [deuterated sodium dodecylsulfate (SDS)] environments. Results suggest the absence of discernible elements of secondary structure in water and methanol. ROESY spectra confirm that Lys-Pro and Arg-Pro peptide bonds are all-trans, but that a significant population of cis Arg-Pro bonds arises in aqueous solution, which increases in the environment of SDS micelles. The conformational ensemble of the peptide is observed to narrow as it becomes bound through its cationic mid-region to SDS micelles, with the accompanying advent of local extended structure. The overall results indicate the inherent conformational flexibility of neurotensin, and emphasize the environmental dependence of conformation in peptides of medium length.  相似文献   
102.
Zusammenfassung Die Bedeutung der Anastomosen zwischen Arteria pulmonalis und Arteria bronchialis und der davon abgehenden arterio-venösen Anastomosen für die Mikroembolie in der Lunge wird dargestellt. Da bei Luftembolie nur sehr selten eine Mikroembolie zustande kommt, müssen für den Übertritt kleiner Luftblasen über die genannten Anastomosen in die Vena bronchialis besondere Verhältnisse gegeben sein. Der Druck in der Arteria bronchialis muß abfallen, so daß über eine Strömungsumkehr Blut und damit möglicherweise auch kleine Luftblasen aus der Arteria pulmonalis über die genannten Anastomosen in die Vena pulmonalis gelangen können.Nach einem Vortrag, gehalten auf der 65. Jahrestagung der Deutschen Gesellschaft für Rechtsmedizin St. Gallen 9.–13.9.1986  相似文献   
103.
目的 探讨产后出血的原因与影响因素。方法 回顾分析收治的产后出血 15 9例 ,数据处理采用χ2 检验。结果 产后出血发生率 3.5 % ,产后 2小时内出血者 88.6 7% ,出血原因宫缩乏力为 6 6 .6 7% ,影响因素有手术产、流产史、分娩史、妊娠合并症及产程延长等 ,统计学处理P <0 .0 1。结论 重视产后出血的影响因素 ,正确评估出血量及产妇产后 2小时留置产房观察是产后出血早期诊断的关键 ,其预防重点在于早期发现并针对不同原因及时正确处理  相似文献   
104.
105.
Three representations of the conditional independences due toMendelian segregation of genes in a pedigree are proposed. Thecomputational costs of performing calculations using the techniqueof peeling with each of these representations is compared byconsidering the weights of triangulations of the graph producedby each representation.  相似文献   
106.
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period.  相似文献   
107.
Two cloned DNA fragments, one derived from an alpha satellite subfamily common to chromosomes 13 and 21, and the other derived from a similar subfamily common to chromosomes 14 and 22, have been used as biotinylated probes in in situ hybridization studies. Under high stringency conditions, chromosome specific centromeric labelling can be obtained. The applications of this technique in clinical situations are illustrated on metaphases from a fetus with trisomy 21, a fetus with trisomy 13, and a child with clinical features of cat-eye syndrome.  相似文献   
108.
格拉斯哥评分的纯数学意义及临床评估价值   总被引:2,自引:0,他引:2  
总结1022例颅脑外伤进行格拉斯哥评分的实践实验,从纯数学意义上评价了评分在临床上的应用价值。指出格拉斯哥评分各参数之间只有15种组合最常见且有临床价值。数学分析表明运动反应最有决定性意义;同时指出格拉斯可评分对患者预后判断有重要评估价值。评分的不足之处在于不能反映瞳孔改变和脑干症状。  相似文献   
109.
This is a retrospective study analysing 5264 patients treated in the burn centre at Gülhane Military Medical Academy from 1 January 1986 to 31 December 1995. Our burn centre is not only the firs, but one of the best established and supported in Turkey. Our present study has the largest patient group of other previously published studies from Turkey. Of the total patients studied, 4464 patients had minor burns and were treated on an outpatient basis and 800 patients had moderate to major burns. Although our centre is in a military area in Ankara, only 1047 (20 per cent) patients were military personnel and the military-related burn causes comprised only 6 per cent of the total. The remaining 4217 (80 per cent of the total patients) were civilians. Flame injuries were also more frequent in military patients than civilians. Minor burns were most common in the age group 0–10 years old (40 per cent) and moderate to major burns in the age group 21–30 years (54 per cent). Scalds were the main cause of paediatric burns. Male patients were dominant. The overall mortality among inpatients was 18.2 per cent and mean total body surface area (TBSA) was 57.6 per cent in patients who died. 134 patients demonstrated inhalation injury and 82 per cent of these patients died. The epidemiological pattern of our patients is similar to that in other studies from developed countries, although some ethnic causative factors could be found. Our study indicates that emergency measures should be taken to prevent flame injuries at military barracks and industrial workplaces and scalding accidents to children at home and throughout the country.  相似文献   
110.
We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease.  相似文献   
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